In 1323 Machteld married the widower Dirk Loef III lord of Kervenheim en Oedt.

[3][1] In the hope of producing a new heir, Machteld's father Gerard then quickly married Elizabeth van Kleef (?-1382) in 1332.

[5] In return Machteld and Dirk promised to help the count with 150 knights and squires at their own cost in times of war.

She successfully defended the economic interests of Brielle against those of Dordrecht, who wanted to establish a monopoly in the trade of certain goods.

[2] After Willem IV of Holland died at Staveren in September 1345, he was succeeded by his sister Margaret of Hainaut.

On 18 April 1346 one of her first acts was to rule that her son Otto V, Duke of Bavaria would succeed to the lordship of Voorne on Machteld's death.

[7] This was not to the liking of Machteld, because the previous settlement left open the possibility that her niece Joan would succeed her.

Whatever the defeat of Margaret of Hainaut, it did not make that the decision to give Voorne to Otto of Bavaria was overturned.

In June 1358 a treaty between Louis the Roman and count Albert of Holland, confirmed the gift to Otto.